隨著互聯網之間的數據傳輸量大幅增加、大量資訊的雲端儲存以及提供多媒體及軟體的雲端服務，這導致大量數據傳輸的速度達到前所未有的需求，而比較於電通訊傳輸系統，光通訊傳輸系統具有更低的能量損耗，並且有更快的傳輸速率，為了實現大量傳輸數據的高頻光訊號傳輸系統，設計一個能將電訊號轉成光訊號且低損耗的高速電光調變器將是一個非常重要的目標。
在本論文中，致力於利用傳輸電極的設計與分析，結合L-shape PN junction的調變區域，製作出操作波段為1550 nm的高頻Mach-Zender矽光學調變器，並在不同元件長度、不同佈值濃度、不同MMI的對稱調變器及對稱與非對稱調變器中進行比較，以找出設計MZI光調變器最佳化參數。
其中由1mm長度MZI光調變器的S參數顯示，經由設計後調變頻寬可高達50 GHz(71 Gb/s)，並且藉由PAM4調變電訊號驅動2 mm長度的MZI調變器可成功調變25 Gboud(50 Gb/s)資料量的PAM4光訊號，最後整合CMOS driver則可成功調變25 Gb/s的OOK光訊號。

In the past decade, a significant increase in Internet access is driven by an abundance of cloud-based storage and computing, high-definition multimedia streaming, and a lot of Internet services. This has resulted in an unprecedented demand in the speed and volume of data transmission. Compared with the electric transmission system, the optical transmission system has lower power consumption and has higher transmission speed. In order to implement a high-speed optical transmission system, designing a high-speed electro-optical modulator that is able to convert electrical signal into optical signal efficiently is an important target.
In this thesis, we focus on the design and analysis of a travelling wave Si Mach-Zender modulator, where the active region is made of a L-shaped PN junction inside a waveguide for the operating wavelength near 1550 nm. Compared with different element length, different implant concentration, different MMI and the symmetric and asymmetric modulator to optimize the parameters of the MZI optical modulator.
The S parameters show that the modulation bandwidths of a 1mm and a 2 mm MZI modulator are 71Gb/s and 47Gb/s respectively, with an employment of a TWE design. The 2 mm asymmetric MZI optical modulator successfully modulates the 25Gboud (50Gb/s) PAM4 signal driven by electrical PAM4. Finally, the MZI optical modulator packaged with a CMOS driver was successfully demonstrated with a modulation speed of 25Gb/s OOK optical signal.

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